1. Field of the Invention
This invention relates generally to animal guards and electrical transformers, and more particularly to an insulated animal guard adapted to be installed on an electrical transformer to prevent animals climbing or perching thereon from causing a short circuit between the transformer and adjacent high voltage power lines.
2. Brief Description of the Prior Art
Electrical power outages caused by animals climbing or perching on electrical transformers is a common problem in the electrical utilities industry. The animal, such as a squirrel or bird climbing or perching on the transformer will sometimes contact a high voltage power line adjacent the transformer with it's tail or wing, which causes a short circuit between the power line and the transformer.
Insulated animal guard devices are known in the art which are installed on power lines or on the crossbars of utility poles to prevent animals from climbing the poles, walking along the high voltage lines or perching on the crossbars. Some of these devices rotate relative to the line or have barbs to discourage climbing, walking, and perching. However, most of these must be installed by hand at close quarters, and require that the power be shut off during installation or removal of the device.
Others have attempted to solve this problem by installing insulated devices on the transformer. One such device is marketed by Preformed Line Products of Cleveland, Ohio. This device is a flat plate made of plastic and has a slot with straight sides which extends inwardly from one side edge and terminates in a circular hole to define a keyhole-shaped slot. There is another circular hole near one corner which is merely used to hang the device when not in use. Because this device does not have any means for receiving an elongate insulated installation tool to install it on a transformer, the only way it can be installed on a transformer is for the installer, positioned at close quarters to the transformer and high voltage lines, to install it by hand, thus placing the installer's hands dangerously close to the transformer and high voltage lines. Because of these shortcomings, it requires that the power be shut down in order to safely install or remove the device.
Recently OSHA and NEC have adopted safety regulations regarding the safe working distance for persons working on high voltage power lines. The recommended minimum distance to be maintained is 2'-1" between the installer and the power line when working on installations over 600 volts.
Most prior art animal guards and insulating devices currently available such as the Preformed Line Products device are designed to be installed within reach of the installer which means they would need to be installed from arms-length plus 2'-1" from the power line or transformer and, thus, they are not particularly adapted to be installed by the installer positioned at the recommended minimum safe working distance.
The present invention is distinguished over the prior art in general by an insulated animal guard device for installation on electrical transformers to prevent animals climbing or perching on the transformer from causing a short circuit between the transformer and adjacent high voltage power lines. The device is a flat member formed of electrically non-conductive material apertured at one end to be releasably engaged on an insulated bushing extending from the upper end of the transformer to retain the device in a generally horizontal position on top of the transformer. The device is apertured at the opposite end to be received and releasably engaged on the hook jaw clamping elements at one end of a hotstick. A lineworker using a hotstick can easily position the device relative to the transformer and engage it with the insulated bushing so that the power lines and transformer need not be de-energized during installation or removal of the device.